CVE-2020-3509: Cisco IOS XE Software for Cisco cBR-8 Converged Broadband Routers DHCP Denial of Service Vulnerability

Published Sep 24, 2020
·
Updated

A vulnerability in the DHCP message handler of Cisco IOS XE Software for Cisco cBR-8 Converged Broadband Routers could allow an unauthenticated, remote attacker to cause the supervisor to crash, which could result in a denial of service (DoS) condition. The vulnerability is due to insufficient error handling when DHCP version 4 (DHCPv4) messages are parsed. An attacker could exploit this vulnerability by sending a malicious DHCPv4 message to or through a WAN interface of an affected device. A successful exploit could allow the attacker to cause a reload of the affected device. Note: On Cisco cBR-8 Converged Broadband Routers, all of the following are considered WAN interfaces: 10 Gbps Ethernet interfaces 100 Gbps Ethernet interfaces Port channel interfaces that include multiple 10 and/or 100 Gbps Ethernet interfaces

Affected Software

2 affected components
Cisco IOS XE=16.7\(1\)
Cisco cBR-8

Event History

Sep 24, 2020
CVE Published
via MITRE·05:51 PM
Data Sourced
via MITRE·05:51 PM
DescriptionSeverityWeakness
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Frequently Asked Questions

1

What is CVE-2020-3509?

CVE-2020-3509 is a vulnerability in the DHCP message handler of Cisco IOS XE Software for Cisco cBR-8 Converged Broadband Routers.

2

What is the severity of CVE-2020-3509?

The severity of CVE-2020-3509 is high with a CVSS score of 8.6.

3

How does CVE-2020-3509 affect Cisco cBR-8 Converged Broadband Routers?

CVE-2020-3509 could allow an unauthenticated, remote attacker to cause the supervisor to crash, resulting in a denial of service (DoS) condition.

4

How can I fix CVE-2020-3509?

To fix CVE-2020-3509, it is recommended to upgrade to a fixed version of Cisco IOS XE Software.

5

Where can I find more information about CVE-2020-3509?

You can find more information about CVE-2020-3509 on the official Cisco Security Advisory page.

Contact

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